Project Summary Rachel Issaka, MD, MAS? long-term career goal is to become an independent researcher and leader in developing, implementing, and evaluating interventions to reduce colorectal cancer (CRC) mortality in medically underserved populations. She has identified improving follow-up of abnormal fecal immunochemical test (FIT) results as a critical issue to address to achieve this goal. This proposal describes a 5-year comprehensive program of training and mentored research for an academic career in health outcomes research. The research agenda is in line with one of NCI?s five scientific goals: to improve cancer prevention and control. In this goal, advancing health care equity in medically underserved populations is an area of special focus. While Dr. Issaka has a strong background in clinical gastroenterology and safety-net systems-level research, this K08 will provide key training in advanced multilevel statistical modeling, qualitative research methods, mixed methods research, and intervention development. FIT is promoted over colonoscopy for CRC screening in federally qualified health centers (FQHCs) and safety-net health systems due to patient preference and limited colonoscopy resources. For FIT-based screening to effectively reduce CRC-mortality, abnormal results must be followed by a diagnostic colonoscopy. However, FQHCs and safety-net health systems do not consistently track follow-up of abnormal FIT results and failure to complete a diagnostic colonoscopy increases CRC-mortality by up to 3-fold. Research suggests approximately 50% of safety-net patients with an abnormal FIT do not complete a diagnostic colonoscopy within 1 year of their result. This highlights the importance of identifying and describing the barriers to diagnostic colonoscopy completion after abnormal FIT results in order to develop effective interventions. The study?s specific aims are: (1) using mixed methods, identify the potentially modifiable patient, provider, and clinic- level barriers to diagnostic colonoscopy in patients with abnormal FIT results in a large safety-net health system; and (2) based upon intervention targets identified in Aim 1, develop a pilot intervention to improve diagnostic colonoscopy completion in a safety-net population with abnormal FIT results. Dr. Issaka?s mentorship team including world-renowned gastroenterologists, health services researchers, qualitative and mixed methods experts and implementation scientists will provide experiential guidance to complement her didactic training. These factors in addition to the supportive research environments at the Fred Hutchinson Cancer Research Center and the University of Washington, will enable her to achieve the proposed project aims. Upon completion of the proposed research and training, Dr. Issaka will submit a competitive R-level grant application to test the pilot intervention in a randomized trial and will possess the skills and experience to make sustained and impactful contributions to reduce CRC-mortality through evidence-based interventions that improve follow-up of abnormal FIT results.